A nurse is providing preconception counseling for a client who is planning a pregnancy. Which of the following supplements should the nurse recommend to help prevent neural tube defects in the fetus?

A. Folic acid: Neural tube defects (such as spina bifida and anencephaly) occur very early in pregnancy, often before a woman knows she is pregnant. Folic acid (Vitamin B9) is essential for the proper closure of the neural tube. The CDC recommends 400 mcg daily for all women of childbearing age. B. Vitamin C: Vitamin C is important for tissue repair and immune function, but it is not linked to the prevention of neural tube defects. C. Calcium: Calcium is vital for fetal bone development and maternal bone health, but deficiency does not cause neural tube defects. D. Iron: Iron supplements are recommended to increase maternal red blood cell mass and prevent anemia, but they do not prevent neural tube defects.